JP2509001Y2 - Wheel train structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement in the wheel train structure of a timepiece in which two or more pointer indicating wheels are arranged on the same axis.

[Prior Art] In recent years, plastic materials have been frequently used for watch parts. Even in the train wheel structure, a plastic base frame, a train wheel bridge, a handle frame, stones, a center pipe, etc. are driven to support the handle of the train wheel. There is.

A conventional example is shown in FIG. Reference numeral 1 denotes a central pipe, which is driven from the lower part of the drawing upwards until it is determined by a brim 1b, and is fixed by caulking 1a on the opposite side. Reference numeral 2 is a second wheel, 3 is a hour wheel, and 4 is a fourth wheel, and each functions as a pointer indicating wheel and is provided with a minute hand 2a, an hour hand 3a, and a second hand 4a. Reference numeral 5 denotes a base frame formed of a plastic material, into which the central pipe 1 is driven and caulked. The wheel train bridge 6 has a structure in which the upper handle of the fourth wheel & pinion 4 is supported. 7 is a dial.

[Problems to be solved by the invention] However, the center pipe driven into the plastic base frame has a pushing force F when the hour hand is attached and when the minute hand is removed.
1. Because of the pulling force F2, you must always crimp on the opposite side of the drive. Upward when there is no caulking,
Even if the needle is driven in either of the downward directions, when the needle is pushed in or when the needle is removed, the center pipe comes off, and there is a problem that the second wheel has no again or a large again, causing squeezing and disengagement of the train wheel.

Therefore, in the present invention, the center pipe is simply fixed by driving it into the plastic base frame without crimping, thereby eliminating the center pipe omission and providing a simplification of the process.

[Means for Solving Problems] A wheel train structure of a timepiece of the present invention guides a second wheel, which is a pointer indicating wheel, the second wheel and hour wheel, and is driven into a base frame formed of a plastic material. In a train wheel structure having a fixed center pipe, the center pipe is driven into the base frame from the center wheel side and has a brim section on the center wheel side, and the brim section is the base frame. The center frame has a cross-section position determined by abutting with the center frame, and the base frame has a cylindrical wheel receiving surface that is convex toward the hour wheel along the edge of the hole into which the central pipe is driven. The surface is characterized by providing a step with the lower surface of the driving portion of the central pipe.

Further, the base frame is characterized in that a cylindrical wheel receiving surface is formed on the entire circumference on the hour wheel side along the edge of the hole into which the center pipe is driven.

[Embodiment] An embodiment of the present invention is shown in FIG. 1 is the central pipe, 2
Is a second wheel, 3 is a hour wheel, and 4 is a fourth wheel. Reference numeral 5 is a base frame, and 5a is an hour wheel receiving surface. 6 is a train wheel bridge, and 7 is a dial.

The center pipe 1 is driven into the plastic base frame 5 downward from above in FIG. 2 and is fixed by interference, and the driving height is regulated by the brim 1b. Lower surface of driving part 1c
Is set at a position lower than the receiving surface 5a of the hour wheel 3 of the base frame 5. Here, when the hour hand 3a is attached to the hour wheel 3, the pushing force F1 is received by the hour wheel receiving surface 5a of the base frame 5 via the hour wheel, and there is a step with the lower surface 1C of the driving portion of the central pipe 1. Therefore, the pulling force does not work on the central pipe 1. When the pushing force F1 is applied more than necessary, it is received by the hour wheel receiving surface 5a. It will bend until it loses its force and will receive a pushing force F1. And when the pushing force F1 is lost, it returns to the original state.

Next, when removing the minute hand 2a to the center wheel & pinion 2, the center pipe 1 receives the pulling force F2 by the center wheel & pinion 2, but the brim 1b of the center pipe 1 does not cause the receiving center pipe 1 to come off.

As described above, by simply driving the center pipe 1 from above and fixing it with the shimeiro, the same function as before can be maintained, and at the same time, the assembling process and the shape of the center pipe can be simplified by eliminating caulking. Becomes In the base frame 5 formed of plastic, the butting burr 5b generated at the center can be allowed, which facilitates the manufacturing of parts. Further, although the present embodiment has been described with respect to the example of the medium three needles, it can be similarly applied to the structure of the medium two needles or four or more needles.

[Effects of the Invention] In the present invention, the lower surface of the driving portion of the center pipe is provided with a step with the receiving surface of the cylindrical wheel of the base frame, so that the force at the time of pushing the pointer is received by the cylindrical wheel receiving surface of the base frame. Since no force is applied to the central pipe, the central pipe can be prevented from coming off, and the assembling process and the parts shape can be simplified.

Further, the base frame receives the hour wheel at the portion immediately adjacent to the hole into which the center pipe is driven, so that the amount of deformation of the hour wheel can be reduced even if a pushing force is applied when attaching the hour hand to the hour wheel. A stable needle attachment is possible.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a train wheel structure of the present invention. FIG. 2 is a sectional view showing a conventional train wheel structure. 1 …… Center pipe 2 …… Second wheel 3 …… Cylinder wheel 4 …… Fourth wheel 5 …… Base frame 6 …… Wheel train 7 …… Dial plate

Claims (2)

(57) [Scope of utility model registration request] 1. A wheel train structure having a center wheel & pinion as a pointer indicating wheel, and a center pipe for guiding the center wheel & pinion and drivingly fixed to a base frame made of a plastic material. Is driven into the base frame from the second wheel side and has a brim section on the second wheel side, and the brim section determines the cross-sectional position of the central pipe by contacting the base frame, The base frame is provided with a convex hour wheel receiving surface on the hour wheel side along the edge of the hole into which the center pipe is driven, and the hour wheel receiving surface is provided with a step from the lower surface of the driven portion of the center pipe. The wheel train structure of the watch characterized by. 2. A utility model registration claim characterized in that said base frame is provided with a convex hour wheel receiving surface on the entire circumference on the hour wheel side along the edge of the hole into which said center pipe is driven. The wheel train structure of the timepiece described in the first item of the range.